When a user accesses web content such as text, images, video and so on using an Internet web portal, the main criterion on which they judge their perceived Quality of Experience (QoE) of the web content is the time it takes to download a web page. If the time is long, then the user will perceive a low QoE; if the time is short then the user will perceive a high QoE. If the user experiences long download-times, then the web portal used to obtain the web content will not attract as many end-users as it could, and so may generate less income from advertisements. Furthermore, the Internet service will be perceived as slow and other service providers may be chosen which leads to a higher churn for the operator.
Fluctuations in throughput from a web portal may be caused by many different factors. Examples of such factors include:                Establishment of new sessions. In this case, the total capacity is shared among all simultaneous sessions, which in turn fluctuates as end-users request content in parallel in an unsystematic way.        Air-interface fluctuations. The throughput to a specific user over a radio interface depends on the interference and the channel quality. The radio interface has an overall power limit which means that the energy required to send a bit to the user will generate a varying Transmission Control Protocol (TCP)-throughput.        
For current networks, all data object download are performed in parallel such that they compete with each other for radio capacity which results in a bad user experience when network load is high.
There are a number of techniques that attempt to improve the download speed from web portals. One well-known technique applied at servers (acting as web portals) is to provide different versions of some or all pieces of content. For example, special versions of the data may be adapted to low resolution terminals such as smartphones. In this case, the web portal recognizes that the client device accessing the data is a mobile terminal and uses different content accordingly. This is typically achieved by using the letter “m” (or the word “mobile” in English or in a local language) as the first label of the domain name, for example m.portal.com. Servers may redirect requests from other domain names to this domain name (i.e., from www.portal.com to m.portal.com) depending on the user agent information (e.g., terminal, browser and OS) in web request headers. Content adapted for smaller displays such as those on smartphones will also be reduced in size resulting in shorter download times under given cellular load conditions.
Another technique that involves some kind of content adaptation is based on parsing html/text files and/or checking the content to be served at the mobile operator side, and then either removing or correcting non-relevant or wrong data in the mark-up language (e.g., comments, scripts), replacing the URL of some references to content that are stored in local caches, and/or optimizing images embedded into HTML pages for mobile displays. This type of technique is described in U.S. Pat. No. 7,853,593, US 2012/0113893, US 2004/0215665 and U.S. Pat. No. 8,181,107.
Another simple, non-intrusive solution is content compression and transfer of compressed content through the air interface. The web browser at the client device can then decompress the compressed content.
An alternative way to improve the download time is to improve the utilization of wireless links which otherwise tend to be reduced as a result of the longer round trip times in wireless networks. A web client may initiate multiple parallel TCP connections to download different pieces of content. The HTTP 1.1 standard provides some optimization along these lines through the HTTP pipelining feature, which allows multiple requests to be sent through a shared TCP connection. This feature is, however, difficult and is therefore not widely implemented in current web browsers.
A further approach to reduce download times is to pre-fetch content
The main idea of another recent technique is to pre-fetch (or push) a larger amount of (possibly compressed) content to a browser at the client device, typically in a single TCP connection to avoid the impact of TCP slow-start for small data volumes. Examples of such this technique are found in US 2006/0271642 and “SPDY: An experimental protocol for a faster web”, http://www.chromium.org/spdy/spdy-whitepaper/.
A further proposed technique is to control the radio resources and to share the radio resources in a latency optimized way, as described in “QoE oriented cross-layer design of a resource allocation algorithm in beyond 3G systems”, Pablo Ameigeiras, Juan J. Ramos-Munoz, Jorge Navarro-Ortiz, Preben Mogensen and Juan M. Lopez-Soler, Computer Communications Volume 33, Issue 5, 15 Mar. 2010, Pages 571-582. Resources in the air-interface are divided unevenly with more resources to web pages that would otherwise suffer from long download times and therefore provide bad user experience.
The common deficiency of all current solutions is that they result in very unpredictable download times and, in many cases, the result is either download times that are too long for an adequate QoE for many web pages, or pages which are truncated, even if there would have been sufficient capacity for the original content. The non-intrusive solutions are not able to reduce download times sufficiently during high load conditions, and the intrusive solutions perform quality-degrading modifications in low-load scenarios even if the network capacity is such that the original content could have been used. If the intrusive solutions are set to moderate/low content modification, the modifications may be too small during high load conditions.
The existing solutions cannot guarantee aggregate (cell-level) QoE optimization of web downloads over all load conditions.